Answer / lal

we can set the actual value & activate a Timer from the DCS , within in the time which set on the DCS we can isolate the transmitter from the line , and it will not affect the process , the timer is used for safety purpose , we cannot activate it more than a limited time.

Answer / muhammad arsalan afzal

isolate the transmitter from the main isolation valve and
follow this procedure.
First of all
1= Close high pressure manifold valve
2= open the equilizing valve
3= than close the low pressure manifold valve.
Mostly we we open equilizer valve when we are isolating
the tx. but what will happen if we close high side pressure
valve before equilizing valve? applied process Pressure is
already there on both sides of the transmitters no extra
pressure will be exerted on the tx because we are only
closing the valve. DP cell demage only in that case if we
purge high or low side before closing the manifold
isolation valves and we start closing the valve without
opening the equilizer.

Answer / vinu joseph

first close the process isolation valve.then slowly equlise the pressure using equalising valve in the manifold.thendrain the transmitter and we can remove it from service

Answer / m.abouraya

1-open the equalizer and then open the isolation valves
(high wth low) and then make the drain

what are the steps to commissioning a DCS system?

2 Answers   BGR Energy,

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why we use 24 vdc in instruments mostly?

2 Answers  

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how to calibrate any tansmiter by loop or hart calibrator

2 Answers  

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i want interview questions about PROCESS CONTROL INSTRUMENTATION , SENSORS AND TRANSDUCERS IF ANY BADY KNOW ABOUT THAT PLEASE SEND TO MY MAIL karumudi1003@gmail.com

8 Answers   Honeywell, Reliance,

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which is type of thermocouple is used to measure 1000deg?

9 Answers  

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where Pirani gauges are uesd in case of pressure measurement?

3 Answers  

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which type signal in & out in dcs

4 Answers  

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A temperature sensor (RTD) connected via a temperature transmitter is adjusted to give an output of 4ma at 60 deg and 20 ma at 600 deg. This output (4-20ma) from the transmitter is connected to an IGBT-inverter to control a high speed (-12,000 to +12,000 RPM) DC motor. And in the inverter it is programmed as, for 4ma the motor speed will be -3,000 RPM and for 20ma the motor speed will be +10,000 RPM. The question is : If the motor speed is +5,500 (RPM), what will be the temperature? (-sign indicates that the motion is in reverse direction).

9 Answers  

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deference between DCS and PLC including date processing and architacture.

11 Answers   Jindal, Shell,

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0 Answers  

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what should be minimum length and size of impulse line for steam flow orifice and feed water orifice? asked by sanjay parihar

1 Answers   Birla,

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